The American Academy of Neurology published on Thursday a study that showed shingles may increase the risk of stroke in later years.
Shingles is caused by the same virus that causes chickenpox. After a person recovers from chickenpox, the virus stays dormant in nerve roots and can reactivate years later as a painful rash.
The study showed that people aged 18 to 40 years old who had shingles were more likely to have a stroke, heart attack or transient ischemic attack years after people who did not have shingles. Patients over 40 years of age who had shingles were more likely to have a heart attack or TIA, but not a stroke, than those who did not have shingles.
Study author Judith Breuer, of University College London, said that increased screening and treatment for stroke risk factors in older patients might explain why they are at lower risk of stroke and TIA following shingles than younger patients.
"Anyone with shingles, and especially younger people, should be screened for stroke risk factors," Breuer said. "The shingles vaccine has been shown to reduce the number of cases of shingles by about 50 percent. Studies are needed to determine whether vaccination can also reduce the incidence of stroke and heart attack. However, what is also clear is that factors that increase the risk of stroke also increase the risk of shingles, so we do not know if vaccinating people can reduce the risk of stroke per se. Current recommendations are that anyone 60 years and older should be vaccinated. The role for vaccination in younger individuals with vascular risk factors needs to be determined."
The study involved 106,600 people who had shingles and 213,200 people who did not have shingles. The participants were reviewed for an average of six years after shingles was diagnosed, and for as long as 24 years.